Closure system for vacuum driers



CLOSURE SYSTEM FOR VACUUM DRYER Filed Sept. 6, 1943 3 Sheets-Sheet 1 war/j? ez'zrewazg April 17, 1945. A. H. HEINEMAN CLOSURE SYSTEM FOR VACUUM DRYER 3 Sheets-Sheet 2 Filed Sept. 6, 1943 A ril 17, 1945. A, H. HEINEMAN CLOSURE SYSTEM FOR VACUUM DRYER Filed Sept. 6, 1 943 '3 Sheets-Sheet s Patented Apr. 17, 1945 'ArnoldI-Il -Heineman; Chicago, IlL-passignor to i The GuarditelCorporation,a corporation of. v

"This'invention' relates to aclosuresystem for a vacuum'drier'and more particularlyto aclo'surfe' system adapted for continuous operation under a steady vacuum while feeding material .to' befd'e hydrated through the system;

The invention is illustrated'in' the drawings, which Fig. l'represents an end elevation of the end of the drier; Fig. 2 'is a side elevation}, Fig.3 is a sectional elevation taken along theline '3--3 in Fig. 1; and Fig. 4 isa' sectional elevation takei'if along the line 4-4 in Fig; 3;

The present closure system is designed artied: larly to be used in drying systems-of the type, (16-, scribed in the application of. Arnold H. Heinemanl Serial NO. 520,773 filed'Fe bruary2, l944,iii whioli a continuous stream of material is passed'throiigh a vacuum chamber under a' consta'nt'lowabs" tef pressure. The present invention'provides means for opening and closing one endof'theyacmim' chamber in order to permit'r'emovalj of dried "ma-jterial"without loss of vacuum. H

The drying system comprises an" elongated chamber l0, one end of which is open. chamber is provided with a numberof vertically'f spaced tiers of h'eating'coil's ll, betweenjwhihi areguides I2 for supporting trays l 3,1whi'ch"'co f tain material, preferably e'ithe'r vegetable. oifi meat. The trays areintrodu'ced tothe'va' u chamber' at the opposite" end thereofan propelled through the chamber by a convey'er system which is shown'in copending application, Serial No.. 520,773, filed February 2, 1944. The details of the.conveyer system are no part of the present invention. The conveyers are indicated at M and are reciprocally actuated by any suitable means (not shown). I

The chamber H1 is maintained at a suitable low absolute pressure, for example, between 50 and 60 millimeters absolute, by any suitable form of evacuating equipment, connection to which is Application 'septem er a, 1943, sriaif vo. some; 401mm. 10134-92) a m 9 :1: re a e h are T e? of the opening.

, Immediately are the vertically slidabl'e' 'panels, s and, as." The,

indicated at l5. The system is preferably operated in an atmosphere of steam and free from air.

The open end of the chamber lflis provided with a lock system 2|, which comprises two closure systems 22 and 23. The inner closure system 22 includes a depending plate 24 and a base v plate 25. These plates reduce the opening in the encircles the lower half 3| of the opening 26 and 55 upper panel ijsli'prbvidea with a. "brac et as (shown in dotted lines in Figure. s togwhicn is attached the chain 39 '(see jeurf ili The lower anel efi'is provlded'with a bracket 4n t'gs pigiir 3), to which the, chain 3 9is alsoattached aftr' being passed over the pulley}! "(see Figurei 4; at

" the bottom andalso Figured) ",Theflower'pariel 3'6.is also provided with a bracket v(shown in dotted lines Figure 3) Q "carrying," a chain" 43 (see Figure 4) which extends overfthe pulley .44; an s" amazed tome 1 bracket 45, an the [u p r pari'elj35; These chains are suitably drilleriin'j orderTto raise g'andf lo'wer thefpaiiels. The preferred method 'of .operation i'sillust'rated in Figs. 1 and 2. Thepu'lleys are, provided witha gear which engages the rack 4T. The rack I is sup.

chains are attached. The movement of pan'el 36 q actuates chainsf 39 ,fwhich'fare attached, to the panel, and fthese chains being" also attached to panel 35fcause it to move, synchronously initlie opposite direction, tliat isfdownwardly: Movement of the pulleys 44 in the opposite direction conversely" lowers the panel 35 and raises the panel 36'. Means for forcingthe panels'35'and 36 are mounted on the side plates of the chamber. This preferably comprises a pair of link bars 5|, to which are pivotally connected a series of bell cranks 52, which are plvotally secured tothe plates 50 by the bolts 53. The link bars 5i are moved vertically by the air cylinder 54. When the link bars 5| are in lowered position, the bell cranks are withdrawn from the door as shown inFig. 2. When the link bars are raised, the outer ends of the bell cranks are pressed against the door panels, thereby bringing the panels into engagement with the gaskets. The

bell cranks are preferably provided with rollers 56. 1

The bell cranks are'not relied upon to secure an airtight connection. Once firm contact has been established with the gasket, and a differential in pressure has been established between the drying chamber and the panels, this pressure forces the panels against the gasket to produce a satisfactory seal.

A second pair of panels and GI are longitudlnally spaced from the inner set of panels to form a lock chamber 62 which is bounded at mam; crea the top and bottom by plates 53 and 64. Within the lock chamber are a vertically spaced series of tray receiving supports 65. Means for evacuating the lock chamber are indicated at 66.

The outer panels 60 and BI are mounted and actuated by a system substantially identical with that employed for the inner panels 35 and 36. A frame is formed by the bars in, H, and 12, which support the gaskets l3 and 14. The upper panel 60 is connected by the chain to the lower panel GI and this chain passes over the sprocket pulley,

16 which is driven by the rack 11 and the air cylinder 18. The lower panel [H is connected by the chain 80 to the upper panel 60 and that chain is carried by the sprocket pulley 8|. Aseries of bell cranks 82, operated by the link bars 83, and driven by the air cylinder 84 functions to press the panels against the gaskets Band 14.

A plate 90 seals the upper panel 35 from ac-. cess to the air and a similar plate 9| performs the same function for the lower panel. Those portions of the operating mechanism which extend through the side walls are suitably provided with stuffing boxes to avoid leakage.

The operation of the device may be explained by starting with the panels 35 and 35 in closed position and the panels 60 and 61 in open posi tion. At this stage the pressure within the chamber I'll will be about 57 millimeters absolute. The panels 60 and SI are then closed by operation of the air cylinder 18, which drives the sprocket wheel 15, lowering the upper panel and raising the lower panel. When the two' panels have been drawn into abutment, the link bars 83 are drawn upwardly thereby pressing the panels against the gaskets 13 and 14. Air is then removed from the chamber through the vacuum line 66. Preferably, steam is introduced toward the close of theevacuaticn through the line 92, in order to wash out all the residual air and re-' place it with an atmosphere of steam atthe same pressure as that in the drying chamber and preferably under superheat.

When this has been accomplished, the panels then again closed, air is admitted to the chamber, the outer panels are released and then raised. The trays are then removed from the lock chamber and the cycle may then be repeated.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom.

.Iclaim:

1. In a vacuum drier; having an open end, a pair of slidably mounted panels, each of which is adapted to close approximately one-half of said open end, a framed member centrally located in the opening and dividing it into two parts, a gasket completely encircling each of said parts, means for evacuating the chamber and means for moving said panels in opposite directions.

2-..In avacuum drying system; an elongated vacuum chamber open at one end, a lock system at said end comprising an air tight extension of said vacuum chamber, an inner-closure for the lock, and an outer-closure for the' lock, the innerclosu're bein'g sealed against air, and each closure comprising a pair or oppositely slidable panels, means for separately actuating each said pair of panels, aframe having a central opening for each of the'panels, a gasket completely encircling each of such openings, and means for pressing the panels into firm engagement with their respective frames.

3'. A drier as set forth in claim 1, in which means are provided for pressing the panel into initial engagement with the gaskets.

4. A vacuum drier, comprising an elongated, rectangular drying chamber open at each end, means for evacuating the chamber, means for closing the in'let end" of the chamber, means for conveying material to be dried through the cham- 0 ber, a lock system at the outlet end of the frame for each or the panels, there being a centrfal opening in each frame, gasket means completely encircling each of said openings, and.

means for pressing the panel's into engagement with their respective'frames, I 4 g ARNOLD H. HEINEMAN.

n elongated chamber, 

